Cisco Email Security Appliance Content Filter Attachment input validation

CVSS Meta Temp Score
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CTI Interest Score
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6.8$0-$5k0.00

A vulnerability has been found in Cisco Email Security Appliance (Anti-Malware Software) (affected version unknown) and classified as critical. Affected by this vulnerability is an unknown functionality of the component Content Filter. The manipulation as part of a Attachment leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability in the attachment scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass configured content filters on the device. The vulnerability is due to improper input validation of the email body. An attacker could exploit this vulnerability by naming a malicious attachment with a specific pattern. A successful exploit could allow the attacker to bypass configured content filters that would normally block the attachment.

The weakness was published 07/06/2019 as cisco-sa-20190703-esa-bypass as confirmed advisory (Website). The advisory is shared at tools.cisco.com. This vulnerability is known as CVE-2019-1921 since 12/06/2018. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available.

Upgrading eliminates this vulnerability.

Productinfo

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.8

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CNA Base Score: 5.8
CNA Vector (Cisco Systems, Inc.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/06/2018 🔍
07/06/2019 +212 days 🔍
07/06/2019 +0 days 🔍
10/18/2023 +1565 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-20190703-esa-bypass
Status: Confirmed

CVE: CVE-2019-1921 (🔍)

Entryinfo

Created: 07/06/2019 10:13 AM
Updated: 10/18/2023 08:26 AM
Changes: 07/06/2019 10:13 AM (40), 07/01/2020 09:18 PM (18), 10/18/2023 08:26 AM (14)
Complete: 🔍

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